Water under floor illusion?

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Guest MrHarmony

Guest MrHarmony

I guess most of you have seen that Doom or Doom II level where you exit by jumping down a hole in the floor, through which you can see the sky. (Can't be arsed to browse the maps to figure out which one it was...)

Kind of cool IMHO, although I'd like to do it with water, or perhaps some other flat texture... (No need to deal with jumping into it, though; it's just for a nice visual effect to improve the sense of where on the may you are.)

Right, this has to be a "floor over floor" trick; the water has to be say 80-200 units below the floor for the right perspective mapping, and the walls on the inside of the hole have to be replaced with an illusion of the water surface continuing in under the real floor, as if the walls were not there. (I'm using an extra sector to implement the upper, normally textured part of the hole, so that it extends slightly below the floor.)

Now, if the lower wall textures in question are removed, the engine (zdoom, at least; not sure about Doom) renders the *higher* floor in place of the wall textures, which, from a rendering POV, seems close enough that one would suspect that there is a way to trick the engine into rendering the *lower* floor (the water) there instead.

(I'd guess the engine keeps drawing "floor" downwards when it doesn't find a wall texture to switch to. Problem is that I'd like it the other way around, as if the same trick was applied upside down, in the ceiling. Which should work, BTW... Must try! :-)

I've tried a few variants, but no success so far. Has anyone done this? If so, does it require a modified source port with "real" floor above floor support, or is it possible with the original Doom and/or Doom II engines, like some of the other 3D illusions?

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Guest MrHarmony

Guest MrHarmony

It is possible. An example of this kind of trick will be at the tutorials section soon. You can also try going to the room over room trick section and downloading ikspecial.zip.

Yeah, I've seen the IK examples, but IIRC, you can't ever see two floors on the same map area at once... (The idea with the one you mentioned is to get real room-over-room architecture, while I need a visual illusion of one floor flat above another.) I might be missing something, though.

And the deep water example *does* have an artifact that happens to look just like what I need... The "hole" where you jump into the water. Is that present with other engines than ZDoom, BTW...?

Either way, I'll play around some with the methods used there and see if I can get it the way I want. Must work now, though... :-( (I wanna' go home and map! *sob*)